Engine



`lune 26, 1928.

H. M.' LEONARD ENGINE Filed Jne 5, 192@ Mmmm Patented .lune 26, 1928i.

UNITED STATES PATENT or FICE. j

HOWARD NI.v LEoNAnn, or soUrH BEND, INDIANgnssIGNon 'ro GERNANDT Moron conroRAmIoN, or

' Applicationwled June 3,

This invention relates to engines, more particularly to engines of-the injection type, and has for its object to provide novel fuel feeding or injecting means acting in a plu-- rality of stages so as to give the charges of fuel greater -opportunity for complete Va orization before they are finally injected lnto. the engine cylinder. It is highly desirable that the successive charges of fuel for an engine of this type be vaporized as completely as possible ina-gaseous medium such as air or steanror exhaust gas so that a rich, homogeneous fuel mixture is injected as a vapor rather than as a spray or liquid into the engine cylinder, this .being of extremely great importance in engines operating at very'high speeds; An important feature of the present invention relates to securing this complete vaporization4 by compressing the mixture of uid and fuel several times, pref erably with an intermediate 4stage of expansion, thus not only giving more time for the fuel to vaporize. but additionall agitating i it and breaking `up the liquid to acilitate its vaporization.

In the arrangement shown in the drawing, there is a fuel-injecting device including two pump plungers, preferably connected with each other in the form of a double-diameter piston, one of which initially mixes and compresses the charges of liuid and fuel and ejects them into an auxiliary reservoir and the other of which withdraws the charges from the reservoir 4and after compressing them again finally injects them into the engine cylinder. y

. Various other features of novelty relate to the particular 'construction of the abovedescribed double-diameter piston, and* to the relative arrangement of the auxiliary reservoir with respect to the other parts of the fuel-injecting means, and to other novel comi binations of parts and desirable particular constructions, which will be apparent from the following ,description of one illustrative embodiment shown in the accompanying 4one of the pump plungers on the line 2-2 of Figure l; A

Figure 3 is a side elevation of one -half of the vfuel-feeding plunger shown in Flgure 1,

cHIcAGo, ILLINOIS, A conronaTIoN or ILLINoIs.

' l. ENGINE.

192e. serial No. 113,362. 5

being in effecta section =onY the line 3-3 of Figure 2; and

Figure 4 is a section ,through the fuelfeeding plunger of F igurel on the line 4 4 of F ignre 2. l The novel fuel-feedingmeans forming the subject-matter of this invention may be used with-an engine ofany desired'type, as for .example a two-cycle crank-case compression engine including an engine cylinder 10 and a piston 12, whichcooperate with a detachable cylinder head 14 to form a 'combustion space 16 when the piston 12 is at the upper end of its stroke. A compression-relief valve 18 may be provided if desired to facilitate `startingA the engine.` -The cylinder 10 may if desired be provided with the usual water jacket 20.

In the cylinder wall, and in the cylinder headf14, there are' formed co-axial openings, the lower part of which forms a pumpcylinder 22 and the upper part of which contains a sleeve 24 forming a smaller pump cylinder 26, the upper end of which is here shown closed with a plug 28 held by a detachable head 30 fastened to the cylinder head :by

vfluid reservoir which may, if desired, contain Abolts or the like 32. Adjacent the smaller a smaller piston 36 grooved or otherwise formed on its bottom to permit the entrance of compressed gases beneath it and held by a spring 38 which is compressed as the piston rises when gases are forced into the reservoir 34 below the piston.4 The bottom end of reservoir' 34communicates b .a passage 40 through the cylinder head an through sleeve 24, with the interior ofI the sleeve 24.

In the largel` pump cylinder 22 there is arranged a pump plunger 42 reciprocated by a suitable cam or eccentric mechanism driven by or from the engine crank shaft or otherwise and prevented from turning by a key 44 or otherwise. This plunger 42 is provided at its upper end with a part 46 formed with1L a dovetailed groove to form a tongue-andgroove joint with the lower ends of two half-plungers 48 and 50 which together form a cylindrical plunger fitting into the smaller pump plunger 26. The half-plungers 48 and 5() are urged apart by means such as coil springs 52 confined between them, into close fitting engagement with the cylinder wall. As best shown in Figure 3, the half-plunger registers atthe upper 24 into the adjacent space 16 of the engine 58 is just below the .passage 40, and thestroke of'the plunger is 'such that in its lowermost position of the cylinder. The passage passage 40 is uncovered while the passage 58 is still closed. The half-plunger 50 is shown formed with a longitudinally extending passage 60, the upper end of which communicates with the passage 40 when the plunger is in its uppermost position.

. The fuel may be injected into the larger pump cylinder 2,2 in any desired manner, as

p for 'example through a passage 62 controlled by a needle. valve 64, the fuel preferably bein i injected just elow sleeve-24. tion the plunger.42 uncovers a passage 66 through which air or steam or exhaust gas or the like may enter the pump cylinder.

In' operation, on the downward stroke of the two plungers the.. larger plunger 42 creates a partial vacuum in the larger pump cylinder22 which sucks a charge of fuel past-the need-le valve 64 into the pump cylinder. `Near the end of its stroke the passage 66 is uncovered andair or other gaseous fluid is drawn intothe partial vacuum to fill the space above the plunger. upward stroke Aof the two plungers the fuel and fiuid in the pump cylinderv 22 are heavily compressed, thus raising the temperature land agitating the mixture and generally facilitating the vaporization lof the fuel in the gaseous fluid, and in the extreme uppermost position of the plunger the passage 60 registers with the passage 40 and the compressed mixture of fluid and fuel is forced into the reservoir 34 below the piston 36 against the resistance of the spring 38. As the plungersy again move downwardly, plunger 48-50 creates a partial vacuum in the smaller pump cylinder 26 until it reaches its lowermost4 position in which the passage 42 is uncovered, ,whereupon the charge of mixed fuel and fluid in the reservoir 34 rushes into the small pump cylinder 26. As the plungers again come up on the next stroke the charge is heavily `compressed in the smaller pump cylinder 2.6 until at the top of the stroke the passage 58 registers with the passage 56 and the fuel is injected by its own pressure into the combustionfspace 16, This takes place just before the engine cylinder l2 reaches the top of its compression stroke and as the cylinder,

at the top of the cylinder orl In its'lowermost posi- On the4 air in the engine cylinder has been raised by its compression to a temperature above. that required to ignite the fuel ignition takes place immediately on the injection of the fuel charge; f r' 70 While one illustrative embodiment hasbe'en' described in detail, it is not my intention to limit the scope of the invention to that particular embodiment for otherwise than by the termsA of the appended claims.

I claim: 1. An engine of the injection type comprising, in combination with an engine means for mixing successive charges of liquid fuel with 'a gaseous fluid, and means for compressing each-'of the successive charges of `fluid and fuel separately. in a plurality of successive stages and then injecting the mixture into the engine cylin- 2,-An enginefof the injection type comprising, in combination with an engine cylinder, a fluid reservoir, means for mixing and compressing a charge of fuel vin a gaseous fluid and forcing the mixture into said reservoir, and means `for withdrawing the .mixture of fluid and fuel from the reservoirand injecting it into the engine g cylinder, one of said means being arranged to operate the other. 95

3. An engine of the injection type comprising, in combination with an engine" cylinder, a fluid reservoir, means for mix-4 ing and compressing a charge of fuel in a i gaseous'fluid and fore-ing the mixture into 1"" said reservoir, and means for withdrawing the mixture of fluid and fuel from the reservoir and compressing it and finally ininjecting it into the engine cylinder, said two means including interconnectedv pump 105 plungers.

4. An engine of -the injection type comprising, in combination with an engine cylinder, means forl mixing `.successive charges of fuel with a gaseous fluid and 1H thereafter compressing the mixed charges, and additional means for further compressing the mixed charges and injecting'them into the engine cylinder.

5. An engine of the injection type hav- 1l5 ing, in combination with an engine cylinder, a double-diameter pump piston, means including the part' of said piston of one diameter for mixing successive charges of fuel with gaseous fluid and compressing E20 f them, andmeans including the part of the cylinder of the other diameter' for again compressing the mixed charges and injecting them into the engine cylinder.

6; An engine of the injection typehav- 125 ing, in combination with an enginev cylinder, two pump 'pistons adjacent said cylinder, a'pump plunger in each cylinder, and a reservoir adjacent the pump cylinders and so arranged that one of the plungers injects the successive fuel charges into rthe land the other i double-diameter reservoir and the other compresses the charges from the reservoir and injects them .in the double-diameter. Vpump cylin into the engine cylinder.

7. An engine having, in combination withy an engine cylinder and means for forming successive separate fuel charges, a plurality of fuel compressors arranged to act successively on said charges theminto said cylinder.

8. An engine having, in combination with; an engine cylinder and means for forming successive separate fuel charges, a plurality of fuel compressors arranged to act successively on said charges and finally to inject thein into said cylinder, together with means permitting expansion of the charges' acted on by one compressor before the action thereon of the next compressor.

9. An engine having, in combination with an engine cylinder, a double-diameter pump cylinder and a double-diameter pump piston therein, and means for receiving charges compressed in the part of the cylinder of larger' diameter and delivering them to the. part of smaller diameter, the `part of the,

piston of smaller diameter being arranged to inject the charges into the vengine cylinder. 1.0. An engine having, in combination with an engine cylinder, a double-diameter pump cylinder and a double-diameter` pump piston therein, and means i-ncluding a separate cylinder containing a spring-loaded piston for receiving charges compressed in the part of the cylinder of larger diameter and delivering them to the part of smaller diameter, the part of the piston of smaller diameter being arranged to inject the charges into the engine cylinder.

11. An engine ha ing, in combination with an engine cylinder, wo compressors and an auxiliary cylinder containing a springloaded piston. one compressorforcing compressed fuel charges into said auxiliary cylinderv against theresistance of said piston,

charges from the auxiliary cylinder and injecting them into the engine cylinder.

12. An engine having, in con'ibination with an engine cylinder, an adjacent pump cylinder paralleling the engine cylinder, a sleeve fitting into the upperpart of the pump cylinder and` forming apump cylinder of smaller diameter and the bottom of which forms a head for an annular lower cylinder space, and a double-diameter piston in the arranged to inject fuel charges intol the engine cylinder.

13. An engine having,

in combination with an engine cylinder, an

adjacent `pump Y cylinder parallelingvthe engine cylinder, a

sleeve fitting into the upper partof the pump cylinder and forming a pump cylinand .finally to injectV `with an engine cylinder, a

compressor receiving the f pump cylinder so l formed, i

formed, arranged to inject `fuel charges into i the engine cylinder, together with a reservoir communicating with vthe upper part of the cylinder when the 'piston is at the lower end of its stroke and with kthe lower part of the cylinder when the piston is at the upper end of its stroke. l

` 14. An engine having, in` combination with an engine cylinder, a pump cylinderv having an and a' lowery part of larger diameter, a double-diameter piston therein, and a reser- -voir communicating with the small-diameter part of the pump cylinder when the piston is at the bottom of its stroke and'with the large-diameter part of the pump cylinder when the piston is at the upper end of its stroke.-

15. An engine having, vin combination pump cyiinder having; an upper part of small diameter and a lower part of larger i diameter,- a

double-diameter piston therein, and a reservoir communicating with the small-diameter part ofthe pump4 cylinder above ,the Aend of the piston when the pistonis at the bottom; of its stroke and with the large-diameter` part lof the pumpcylinder through a passage upper part of small diameter in the iston when the piston is at the upper end of its stroke.

16. A' fuel-injecting` pump having a. 100

double-diameter piston including a lower partof'large diameter and an upper part in two separate pieces urged yieldingly apart and connected to the lower part.

17. A fuel-injecting pump having a double-diameter pistonl including au lower part of large diameter andan upper part in two separate pieces vurged yieldingly apart and having tongue-and-groove con-' nection with the lower part. l

18.4 That method of preparing and injecting fuel into an engine which comprises the steps of mixing and compressing each fuel charge with a charge of gaseous medium thereafter, allowing. partial expansion of the fuel mixture, and vfinally additionally 'compressing the fuel'inixture `and injecting it into the engine.

19. That method of preparing and injecting fuel into anengine which comprises the steps of mixing each fuel charge with a charge 0f gaseous medium and thereafter compressing it, and additionally-f compressing the fuel mixture and injecting 'it into the engine.

In testimony whereof, I have hereunto signed my name. 1 

